This experiment was conducted to explore the efficacy of -tocopherol acetate (AT), a commercial supplement containing tocopherols, in commercial broilers. Three hundred and thirty Ross broiler chicks (4-d old) were randomly distributed and allotted to five dietary treatments for six weeks. Each treatment comprised 3 pens as replicates containing 22 chicks per pen. The five dietary treatments were: 0 mg/kg AT (negative control); 10 mg/kg AT; 50 mg/kg AT; 100 mg/kg AT; and 200 mg/kg AT; respectively, supplied totally by the supplement under study. Supplementation of AT improved weight gain significantly (p<0.05), with higher values in the 100 and 200 mg/kg AT fed group than the control during all phases of study, but feed intake remained unaffected. The nutrient digestibility studies conducted after 15 and 35 days of experimental feeding showed significantly higher digestibility of CP, ether extract and gross energy, in these two groups over the control diet. Carcass traits like dressing percentage and the color of the breast meat did not differ significantly due to treatments, but significantly (p = 0.0152) lower abdominal fat percent was noted in the 200 mg/kg fed group. Higher (p = 0.0003) tibia bone strength was noticed in groups fed diets above 50 mg/kg AT because of higher bone mineral content. The serum levels of tocopherols were not influenced but the muscle tocopherols content showed a positive linear trend with the dietary levels supplemented. The thio-barbituric acid reactive substances (TBARS) level in meat also suggested that supplemental AT has a protective role in rancidity. Overall, it could be concluded that AT supplementation at higher levels was found beneficial for growth and increased chicken meat quality.

Mazija, H., V. Serman, N. Mas and E. Prukner-Radovicic. 1992. Immune response as marker of needs for vitamins in chickens. 4. The influence of vitamin E on the immune response and development of immune system organs in chickens, Krmiva. 34:77-81